Method of making pressed-glass articles.



O. A. MYGATT.

METHOD OF MAKING PRESSED GLASS ARTICLES.

APPLICATION FILED MAR. 21, 1903.

925,824. v Patented June 22, 1909.

PIGJ. \b

PICAL flow under'the action of a mg press, whereby a lesser .To all whom it may mm:

. usel'ul'lmprovements in Be Il/liIlOWH that I, OrIsA. Mroixrr, citiizgn of the United States, residing at New Xork, in the county of New York and State of New-York, have invented certain new and Methods of Making Pressed-Glass Articles, of which the following is a specification.

his invention relates to a method of making 'ressed glass articles.

Tie object of the invention is to shorten the distance which the plastic glass must plunger in a moldquantity of material IS necessary, and where by thinner articles with;more sharply defined surfaces may be I produced.

' mouth of mold.

The invention consists in certain manipulationsand operations, as will be ex lained.

Figure 1 is .a section of a rolling lied and roller, with a batch of plastic material on the bed; Fig. 2 is' a broken elevation of a plunger, such as may be employed in a glass mold. with which the plunger of Fig. 2 is supposed be employed, showing plastic plate over Fig. 4 is a section of mold andplunger, showing mode of operation on plunger and mold.

' the plastic sheet of glass.

5 I to assist in explaining the 10 figures are merely diagrams supposed invention to persons skilled in the art, and are not intended to represent precise structures or proportions.

lleretol'ore, in pressing glass in molds, it has been usual to place an irregular mass of hot, plastic glass in a mold, and press the same to form by the action of a plunger. The mass of glass, found by guess or by weight-to be sullicient for the purpose, has been )laced in the bottom of a mold, say mold ii, and when plunger B is brought down into the mold, the plastic mass is underpressure, and flows into the space between the As the central part ol' the plunger first encounters the glass, and presses the same outwardly, a considerable part of the hot plastic glass is compelled to flow nearly the whole distance from the center to the extreme edge 01' the mold. The mold and plunger have the glass and it becomes less plastic as it grows cooler. Thus most molded articles are thickest at about the part lirst exposed to the-plunger action, and the article, having been molded at uneven temperatures, is sub- METHOD oF iviAkme rREssEnGLAss ARTICLES.

Specification of Letters Patent. Application fi led much 21, 1903.

Fig. 3 is a vertical section of a mold,

a tendency to cool rns'rarnnr enrich.

oris A. MYGATT, or new roan, n. Y.

Patented June 22, 1909. Serial No. 148,870.

[.ject to internal strains. 7 More glass is. used for most articles than desirable, and the glass when partially cool, away from t be conter of the mold, is not capable ol' 'llowing so i completely mto fine depressions H) the mold,

- thus giving poor definition. l overcome I these objections and dilliculties to a great I extent as follows: Taking a mass ol' plastic I glass, G, found by weight or otherwise to be l sull'icicnt for the purpose of producing the l desired article, the same i placed on a molding table (I, prel'erably ol' carbon, and the mass is rolled out by a roller, as D, to such form and size as the mold makes necessary. For convenicucc and economy, the rolled sheet will generally approximate the diameter of the article to be molded. The sheet G so rolled out, is placed over the mouth of the mold, as in Fig. 3. It will generally immediately sag, of its own weight, and in course of so sagging the material will flow or be l drawn to some extent away l'rom the center,

[that art of the sheet becoming thinner.

I The plimger B is inmnjalii'vtcly brought down i on the sheet, acting in this case in nearly the {same direction that gravity acts, to impel the material to and into the mold. The material ot' the sheet has but a short distance to flow under the pressure of the plunger, to reach the sides of the mold, and any depresl sions in the mold, such, for instance, as are I indicated at o A much thinner article can be so molded, and one having better definition" of fine or ornamental lines, than in glassware molded in the usual way.

The plunger B may have its surface ribbed or. otherwise formed in any way which will permit the withdrawal of the plunger and delivery of the article from the mold, and

l any known form of plunger, such as a coll lapsible plunger may be used.

I While I have described the action of the plunger as being in downward direction, this l is not necessary, as it is obvious that a substantially similar result will be reached if the mold and plunger are inverted. In either case he plunger will begin to act by its central portion, and-the flow of the glass within the mass will be to a less distance it first reduced to approximately sheet form before i pressing by a plunger, into a mold.

l It has been common heretofore to form a plate ol'hot plastic glass, and then to force or g expand the same into a mold by air pressure.

t In such case the air will l'orce the sheet into l depressions in the mold by elastic pressure,

leaving a similar depression in the interior of then sagging the hot sheet bygrayity to draw the vessel, and never producing sharp and l the material away from the central portion, Well defined surfaces on the glass, such as must follow from the pressure of a rigid instead of an elastic plunger.

' \Vhat I claim is:

The herein described method which consists in rolling a mass of hot glass to a sheet then compressing the glass sheet-by a plunger into its final form.

l in presence of two witnesses;

p H ,OTIS-A. MYGATT.

Witnesses: s

approximately the size of the article to be S. W.FERGUSON,

-W. A. DOREY.

10 produced, then placing it over a cavity mold,

In testimony whereof I- my signature 15 

